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Basement Flooding Right Now: What to Do First

Updated October 2026 · Sources: U.S. Census, USDA NRCS, NOAA, NWS · Methods

Short answer

Stay out of standing water until power to the basement is off, and assume river or sewer water is contaminated. Then find the source: a failed sump pump, a backup at the floor drain, groundwater seepage or river water. Remove water, photograph everything for insurance, and dry the space within a day or two. Call a professional for anything electrical or for floodwater cleanup.

Do this first

  1. Don’t step into standing water until power to the basement is off.
  2. If the water came up the floor drain or from the river, treat it as contaminated.
  3. Photograph and video everything before moving anything.

1. Stay safe

  • Electricity. If outlets, cords or the panel are in or near the water, shut off power at the main breaker only if you can reach it from a dry spot. Otherwise call the utility or an electrician.
  • Gas appliances. If the furnace or water heater was under water, don’t restart it until a professional checks it.
  • Contamination. River water and sewer backups carry sewage and chemicals. Wear boots and gloves, and keep children and pets out.

2. Find the source

What you seeLikely sourceGo to
Pit full, pump silent or hummingSump pump failure or power outageSump pump repair
Water from the floor drain with an odorCombined sewer backupSewer backup or groundwater?
Water along walls or through floor cracksGroundwaterFloor-wall joint
Water over window wells or through doors, river risingOverland floodingWhite River flooding

If the river is rising, follow the City of Anderson’s flood instructions. The city says the White River begins to overflow at about 10 feet.

3. Stop more water if you safely can

  • Restart the sump pump if the GFCI tripped or the float is stuck, or run a backup or portable utility pump.
  • Don’t use sinks, showers or toilets during a sewer backup.
  • Clear snow, ice or debris from a blocked sump outlet.

4. Document

Take photos and video of the water, the damage, the pump and anything you throw out. Write down dates and times. Insurance and assistance programs ask for this.

5. Dry out within a day or two

  • Remove water with a pump or wet-dry vacuum.
  • Pull up soaked carpet and padding. Cut out wet drywall and insulation about a foot above the water line.
  • Run fans and dehumidifiers continuously.
  • Clean and disinfect hard surfaces that contaminated water touched.

6. Then fix the cause

Once the basement is dry, find out why water got in. On Anderson’s ground, that’s often a sump pump without a backup, an old footing drain on a high water table, or a combined sewer backup. The problem guides help narrow it down.

Who to call for what

SituationCall
Water near outlets, cords or the electrical panelThe electric utility or an electrician
Gas smell, or a gas appliance that was under waterThe gas utility, from outside the house
Sewage coming up the floor drainA plumber, and the city’s sewer utility
Large or contaminated cleanupA water damage restoration company
Pump failed or can’t keep upA plumber or waterproofing contractor; see sump pump repair
Seepage that returns after the cleanupA waterproofing contractor; see interior drain tile
A claimYour insurance company, with your photos

Insurance, briefly

Standard homeowners policies usually exclude flood damage, and sewer or drain backup is often covered only by an added endorsement. Read your policy’s declarations page or call your agent before throwing out damaged items, and keep receipts for pumps, fans and cleanup supplies. If you’re in a mapped flood area, our flood zones page explains what that means for insurance.

Questions Anderson homeowners ask

Can I go into a flooded basement?

Not until you're sure the power to that area is off. If the panel is in the basement or you'd have to stand in water to reach it, call the electric utility or an electrician.

Who cleans up after floodwater?

Water damage restoration companies handle extraction, drying and contaminated-water cleanup. A waterproofing contractor fixes the reason water got in, after the cleanup.

How fast does mold start?

Mold can start growing within a day or two on wet materials. Remove soaked carpet, padding and drywall promptly and dry the space with fans and dehumidifiers.

How fast does mold start after a basement floods?

Mold can start growing on wet drywall, carpet and wood within a day or two. That's why drying out quickly, and removing soaked porous materials, matters more than anything else after the water is gone.

Not sure what you are dealing with?

Match what you see to the likely cause, then check typical costs before anyone gives you a quote.

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